To provide a low cost and a high reliable vacuum valve which can improve the production efficiency and the vacuum tightness of the vacuum valve, and a vacuum circuit breaker using the vacuum valve. Inside a insulating housing 1, a pair of separable conductors in the central axial direction of the sealed vacuum vessel composed of a stationary conductor 3 and amovable conductor 5 are disposed. A stationary conductor 3 having an external surface being broader than a contact area of the separable conductors 3, 5 is jointed to the lower end portion 1B of the insulating housing 1 and the lower end portion 1B of the insulating housing 1 is sealed thereby.